diff options
author | Peter Ujfalusi <peter.ujfalusi@ti.com> | 2020-01-07 14:45:32 +0300 |
---|---|---|
committer | Jonathan Cameron <Jonathan.Cameron@huawei.com> | 2020-01-12 14:34:08 +0300 |
commit | a9ab624edd9186fbad734cfe5d606a6da3ca34db (patch) | |
tree | 2c9fc9c135f4df509e78bc8b71bc9f188f937fc0 /drivers | |
parent | e895bc1ebb31750f3baa74e074617d3cc5d0cee2 (diff) | |
download | linux-a9ab624edd9186fbad734cfe5d606a6da3ca34db.tar.xz |
iio: adc: stm32-dfsdm: Use dma_request_chan() instead dma_request_slave_channel()
dma_request_slave_channel() is a wrapper on top of dma_request_chan()
eating up the error code.
By using dma_request_chan() directly the driver can support deferred
probing against DMA.
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Acked-by: Olivier Moysan <olivier.moysan@st.com>
Acked-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/iio/adc/stm32-dfsdm-adc.c | 21 |
1 files changed, 17 insertions, 4 deletions
diff --git a/drivers/iio/adc/stm32-dfsdm-adc.c b/drivers/iio/adc/stm32-dfsdm-adc.c index e493242c266e..74a2211bdff4 100644 --- a/drivers/iio/adc/stm32-dfsdm-adc.c +++ b/drivers/iio/adc/stm32-dfsdm-adc.c @@ -1383,9 +1383,13 @@ static int stm32_dfsdm_dma_request(struct iio_dev *indio_dev) { struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); - adc->dma_chan = dma_request_slave_channel(&indio_dev->dev, "rx"); - if (!adc->dma_chan) - return -EINVAL; + adc->dma_chan = dma_request_chan(&indio_dev->dev, "rx"); + if (IS_ERR(adc->dma_chan)) { + int ret = PTR_ERR(adc->dma_chan); + + adc->dma_chan = NULL; + return ret; + } adc->rx_buf = dma_alloc_coherent(adc->dma_chan->device->dev, DFSDM_DMA_BUFFER_SIZE, @@ -1509,7 +1513,16 @@ static int stm32_dfsdm_adc_init(struct iio_dev *indio_dev) init_completion(&adc->completion); /* Optionally request DMA */ - if (stm32_dfsdm_dma_request(indio_dev)) { + ret = stm32_dfsdm_dma_request(indio_dev); + if (ret) { + if (ret != -ENODEV) { + if (ret != -EPROBE_DEFER) + dev_err(&indio_dev->dev, + "DMA channel request failed with %d\n", + ret); + return ret; + } + dev_dbg(&indio_dev->dev, "No DMA support\n"); return 0; } |